Answer:
Consider this balanced chemical equation:
2 H2 + O2 → 2 H2O
We interpret this as “two molecules of hydrogen react with one molecule of oxygen to make two molecules of water.” The chemical equation is balanced as long as the coefficients are in the ratio 2:1:2. For instance, this chemical equation is also balanced:
100 H2 + 50 O2 → 100 H2O
This equation is not conventional—because convention says that we use the lowest ratio of coefficients—but it is balanced. So is this chemical equation:
5,000 H2 + 2,500 O2 → 5,000 H2O
Again, this is not conventional, but it is still balanced. Suppose we use a much larger number:
12.044 × 1023 H2 + 6.022 × 1023 O2 → 12.044 × 1023 H2O
These coefficients are also in the ratio of 2:1:2. But these numbers are related to the number of things in a mole: the first and last numbers are two times Avogadro’s number, while the second number is Avogadro’s number. That means that the first and last numbers represent 2 mol, while the middle number is just 1 mol. Well, why not just use the number of moles in balancing the chemical equation?
2 H2 + O2 → 2 H2O
is the same balanced chemical equation we started with! What this means is that chemical equations are not just balanced in terms of molecules; they are also balanced in terms of moles. We can just as easily read this chemical equation as “two moles of hydrogen react with one mole of oxygen to make two moles of water.” All balanced chemical reactions are balanced in terms of moles.
Explanation:
The answer would be a. C2H4(ethylene)
1C2H4+3O2~>2CO2+2H2O
Answer:
208.7°C was the initial temperature of the limestone.
Explanation:
Heat lost by limestone will be equal to heat gained by the water

Mass of limestone = 
Specific heat capacity of limestone = 
Initial temperature of the limestone = 
Final temperature =
=T = 51.9°C

Mass of water= 
Specific heat capacity of water= 
Initial temperature of the water = 
Final temperature of water =
=T = 51.9°C



On substituting all values:


208.7°C was the initial temperature of the limestone.
Answer:

Explanation:
Ionic bond is a bond between metals and non-metals with strong forces of attraction between charged ions.